ABSTRACT
Resumo Objetivo: Avaliar a eficácia na adaptação de lentes de contato em relação à melhora da acuidade visual em pacientes portadores de ceratocone. Métodos: Foi realizado um estudo retrospectivo, através de revisão de prontuários médicos, em 175 pacientes (326 olhos) portadores de ceratocone, atendidos no período de março/2004 a junho/2015. Foram coletados os dados sobre sexo, idade, número de olhos adaptados, severidade do ceratocone e acuidade visual com óculos e com lentes de contato. Resultados: Dos pacientes avaliados, 100 pacientes (57,4%) eram do sexo feminino e 75 pacientes (42,6%) do sexo masculino. Dos olhos classificados, 267 (81,9%) tinham ceratocone moderado (45 a 52D). A faixa etária mais frequente foi de 10-39 anos (84%) e a taxa de sucesso ao fim do tratamento foi de 92,3% (acuidade visual boa ou satisfatória). Conclusão: A adaptação de lentes de contato mostrou-se eficaz em proporcionar importante melhora da acuidade visual em pacientes portadores de ceratocone.
Abstract Objective: To evaluate the efficiency of the contact lens adaptation in relation to the improvement of visual acuity in patients with keratoconus. Methods: A retrospective study of 175 patients (326 eyes) with keratoconus was carried out from March 2004 to June 2015. Data on sex, age, number of adapted eyes, keratoconus severity, and visual acuity with glasses and contact lenses were collected. Results: Of the classified eyes, 267 (81.9%) had moderate keratoconus (45 to 52D). The most frequent age group was 10-39 years of age (84%) and the success rate at the end of treatment was 92.3% (good or satisfactory visual acuity). Conclusion: Adaptation of contact lenses was effective in providing important improvement of visual acuity in patients with keratoconus.
Subject(s)
Humans , Male , Female , Infant, Newborn , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Adaptation, Physiological , Contact Lenses , Keratoconus/rehabilitation , Medical Records , Retrospective Studies , Accommodation, Ocular , Keratoconus/classificationABSTRACT
ABSTRACT Purpose: Keratoconus is characterized by bilateral asymmetrical corneal ectasia that leads to inferior stromal thinning and corneal protrusion. There is currently a lack of consensus regarding the most efficacious method for fitting contact lenses in patients with keratoconus, given the various topographical patterns and evolution grades observed in affected populations. The purpose of the present study was to evaluate the association between keratoconus evolution grade and topography pattern and the type and design of fitted contact lens. Methods: We performed a retrospective analysis of contact lenses fitted in a total of 185 patients with keratoconus (325 eyes). Keratoconus was classified as either grade I, II, III, or IV based on keratometry and cone morphology (nipple, oval, globus, or indeterminate) results. Results: A total of 325 eyes were evaluated in the present study. Of the 62 eyes classified as grade I, 66.1% were fitted with monocurve contact lenses. Of the 162 eyes classified as grade I and II, 51%, 30%, and 19% were fitted with adapted monocurve rigid gas-permeable contact lenses (RGPCL), bicurve lenses, and others lens types, respectively. Bicurve lenses were fitted in 52.1% and 62.2% of eyes classified as grade III and IV, respectively. Of the eyes classified as grade III and IV, monocurve and bicurve RGPCL were fitted in 26% and 55%, respectively. In eyes with oval keratoconus, 45%, 35%, and 20% were fitted with monocurve lenses, bicurve lenses, and other lens types, respectively. In eyes with round cones (nipple morphology), 55%, 30%, and 15% were fitted with bicurve lenses, monocurve lenses, and other lens types, respectively. Conclusion: Monocurve RGPCL were most frequently fitted in patients with mild to moderate keratoconus and oval cones morphology, while bicurve lenses were more frequently fitted in patients with severe and advanced keratoconus. This was probably because bicurve lenses are more appropriate for round cones due to increased corneal asphericity.
RESUMO Objetivo: O ceratocone é uma ectasia corneana bilateral e assimétrica que leva a afinamento corneano inferior e protrusão da córnea, não existe consenso sobre qual é o melhor caminho para adaptar lentes de contato em pacientes com ceratocone, considerando seus diferentes padrões topográficos e graus de evolução. O objetivo desse estudo é associar o grau de evolução e padrão topográfico com o tipo/desenho da lente adaptada. Métodos: Análise retrospectiva das lentes de contato adaptadas em 185 pacientes com ceratocone (325 olhos) no Departamento de Lentes de Contato. O ceratocone foi classificado de acordo com a ceratometria em graus I, II, III e IV e de acordo com a morfologia em cone redondo, oval, globoso e indeterminado. Resultados: Foram avaliados 325 olhos. Em 66,1% dos olhos com grau I foi adaptada lente monocurva. Dos 162 olhos classificados como graus I e II foram adaptadas lentes monocurva em 51%, bicurva em 30% e outros em 19%. Em relação aos olhos grau III, em 52,1% foram adaptadas lentes bicurvas e o mesmo aconteceu em 62,2% dos olhos com grau IV. Apenas 26% dos olhos grau III ou IV receberam lentes monocurva, com necessidade de bicurvas em 55%. 45% dos cones ovais foram adaptados com lentes monocurva, 35% com bicurvas e 20% com outros tipos, enquanto 55% dos cones redondos foram adaptados com lentes bicurvas, apenas 30% com monocurvas e 15% com outros desenhos. Conclusão: Lentes de contato rígida gás-permeável (LCRGP) monocurvas são mais frequentemente utilizadas em ceratocones leves e moderados e em ovais, enquanto bicurvas são mais usadas para casos graves e avançados e em cones redondos.
Subject(s)
Humans , Adolescent , Adult , Young Adult , Prosthesis Fitting/instrumentation , Contact Lenses , Contact Lenses, Hydrophilic , Equipment Design , Keratoconus/classification , Visual Acuity/physiology , Retrospective Studies , Corneal Topography , Keratoconus/pathology , Keratoconus/rehabilitationABSTRACT
PURPOSE: To evaluate the performance of support vector machine, multi-layer perceptron and radial basis function neural network as auxiliary tools to identify keratoconus from Orbscan II maps. METHODS: A total of 318 maps were selected and classified into four categories: normal (n = 172), astigmatism (n = 89), keratoconus (n = 46) and photorefractive keratectomy (n = 11). For each map, 11 attributes were obtained or calculated from data provided by the Orbscan II. Ten-fold cross-validation was used to train and test the classifiers. Besides accuracy, sensitivity and specificity, receiver operating characteristic (ROC) curves for each classifier were generated, and the areas under the curves were calculated. RESULTS: The three selected classifiers provided a good performance, and there were no differences between their performances. The area under the ROC curve of the support vector machine, multi-layer perceptron and radial basis function neural network were significantly larger than those for all individual Orbscan II attributes evaluated (p<0.05). CONCLUSION: Overall, the results suggest that using a support vector machine, multi-layer perceptron classifiers and radial basis function neural network, these classifiers, trained on Orbscan II data, could represent useful techniques for keratoconus detection.
Subject(s)
Adult , Female , Humans , Male , Artificial Intelligence , Corneal Topography/instrumentation , Keratoconus/classification , Keratoconus/diagnosis , Diagnosis, Computer-Assisted/methods , Neural Networks, Computer , ROC Curve , Sensitivity and SpecificityABSTRACT
Com o objetivo de estudar os subtipos topográficos do ceratocone, os autores estudaram através de um sistema de análise topográfica computadorizada 59 córneas de olhos näo operados de 34 pacientes com ceratocone. Todos os pacientes apresentavam achados clínicos compatíveis com ceratocone em pelo menos um dos olhos ou haviam sido submetidos a ceratoplastia por ceratocone no olho contralateral. A análise topográfica corneana foi realizada em ambos os olhos ou haviam sido submetidos à ceratoplastia por ceratocone no olho contralaterl. Quanto aos subtipos topográficos, os autores encontraram padräo em 8 simétrico (2/57; 3,51 por cento); 8 assimétrico (13/57; 22,81 por cento); 8 distorcido (15/27 por cento) e irregular (9/57; 15/79 por cento) ..